Is Class A still the king of tone?

At the end of the day I think that things are really simple! It must be a matter of taste and taste alone. I'm sure some of you guys come from class A amps or tube SET or push pull towards class AB or even D and some the other way around. It's about what we like and how years of experience have changed us in one way or another.
For me... I started with class D (Jeff Rowland), then passed on to class AB (BAT VK-655SE although it probably never left class A for AB) and then on to my class A Vitus SS-010 Mk2. I can honestly say that now if I were to upgrade my amplification I would probably head towards a Vitus SIA-025 Mk2, a LAB12 Suara Mk2 or a Jadis I-70 integrated. So I'd stick to class A.
Some of you might head the other way around. And that's fine! That's absolutely normal! So I don't get the big fuss around here.... It's all about what we've come to apreciate in sound and music!
 
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atmasphere said:
If you look a distortion vs frequency, you can find a lot of correlation with what we hear. If the amp has feedback but lacks the gain bandwidth product to support that feedback value properly, the distortion will start to rise at a certain frequency along a 20dB/decade slope. This can cause higher ordered harmonics to be unmasked. This is a reason (not the only reason) that feedback has gotten an undeserved bad reputation. Most tube amps do not have the gain bandwidth product to support a lot of feedback although there are a few outliers. A lot of solid state amps don't either FWIW.
Click to expand...

Unlike yourself, I'm no engineer, but what you say certainly rings true from what I've manage to glean from what you and others have said..

Seems to me that assertions from likes of Bruno Putzey amount to ... "If a little feedback is the problem, a lot of more is the solution".. (Feedback reduces all harmonics (including high-order: something apparently lost on Nelson Pass and many others.) But I, a layman, understand the one have to have enough high "open loop" gain to support a lot of feedback, and as I believe you're saying, that this gain must be continuous across a wide bandwidth of frequencies.

I think in terms of measurements I'd like to see harmonic distortion spectra at more than one as usually provided, typically 500 or 1000 Hz, say 100 Hz and 5000 Hz.

Also I wonder how bandwidth affects transient response? We don't see rise time numbers or even square wave plots as often as we used to .. but I don't pretend to understand what supports good transients or what I call "microdynamics".
 
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